Autism spectrum disorder (ASD) comprises a group of neurodevelopmental disorders characterized by social deficits and stereotyped behaviors. Despite intensive research, its etiopathogenesis remains ...largely unclear. Although studies consistently reported dopaminergic anomalies, a coherent dopaminergic model of ASD was lacking until recently. In 2017, we provided a theoretical framework for a "dopamine hypothesis of ASD" which proposed that autistic behavior arises from a dysfunctional midbrain dopaminergic system. Namely, we hypothesized that malfunction of 2 critical circuits originating in the midbrain, that is, the mesocorticolimbic and nigrostriatal pathways, generates the core behavioral features of ASD. Moreover, we provided key predictions of our model along with testing means. Since then, a notable number of studies referenced our work and numerous others provided support for our model. To account for these developments, we review all these recent data and discuss their implications. Furthermore, in the light of these new insights, we further refine and reconceptualize our model, debating on the possibility that various etiologies of ASD converge upon a dysfunctional midbrain dopaminergic system. In addition, we discuss future prospects, providing new means of testing our hypothesis, as well as its limitations. Along these lines, we aimed to provide a model which, if confirmed, could provide a better understanding of the etiopathogenesis of ASD along with new therapeutic strategies.
Schizophrenia presents a complex mental health challenge, often inadequately addressed by existing antipsychotic treatments, leading to persistent symptoms and adverse effects. Hence, developing ...alternative therapeutic approaches is crucial. Cannabidiol (CBD), a nonpsychoactive compound in Cannabis sativa, has been extensively explored for its therapeutic potential in treating psychiatric disorders, including schizophrenia. CBD exhibits antipsychotic, anxiolytic, and neuroprotective effects. However, distinguishing the individual effects of CBD and THC remains challenging. Therefore, this review aims to critically analyze the potential role of CBD as an adjunctive therapy in schizophrenia treatment. The therapeutic action of CBD may involve activating the 5-hydroxytryptamine 1A receptors and suppressing the G-protein-coupled receptor 55, thereby affecting various neurotransmitter systems. Additionally, the anti-inflammatory and antioxidative effects of CBD may contribute to alleviating neuroinflammation linked to schizophrenia. Compared to typical antipsychotics, CBD demonstrates a lower incidence of side effects and it exhibited favorable tolerability in clinical trials. A 2012 clinical trial demonstrated the efficacy of CBD in reducing both positive and negative symptoms of schizophrenia, presenting a safer profile than that of traditional antipsychotics. However, further research is needed to fully establish the safety and efficacy of CBD as an adjunctive treatment. Future research directions encompass exploring detailed antipsychotic mechanisms, long-term safety profiles, interactions with current antipsychotics, optimal dosing, and patient-specific factors such as genetic predispositions. Despite these research needs, the potential of CBD to enhance the quality of life and symptom management positions it as a promising candidate for innovative schizophrenia treatment approaches.
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Patients diagnosed with unipolar disorder usually experience impaired cognitive functioning during an acute depressive episode. The purpose of the current study was to investigate the association of ...specific clinical factors with cognitive dysfunction in a group of major depressed patients. 65 subjects diagnosed with recurrent major depressive disorder were evaluated during an acute episode. The cognitive functions were assessed with neuropsychological tests for attention and processing speed, memory, verbal fluency, psychomotor speed and executive functions. Hamilton Depression Rating Scale - 17 items was used to quantify the severity of depression. Clinical variables consisted in age at onset, number of previous depressive episodes, presence of psychotic symptoms or suicide attempts. The group had a mean age of 48.48 years, with predominance of females, with a history of 5.43 episodes and associated psychotic symptoms (23.1%) and suicide attempts (20%). Cognitive domains for which we found significant results (
p
< 0.05) were executive functions and attention, being associated with the number of previous depressive episodes. Psychomotor speed was significantly associated with the severity of depression. Also, patients with psychotic symptoms obtained altered results for psychomotor speed and verbal memory. For almost all cognitive domains we found significant statistical association with different clinical aspects, such as number of depressive episodes, severity of depression, presence of psychotic symptoms and suicide attempts. Since each of them had an influence over cognition, further studies involving larger samples are necessary to establish if there is a direct relationship between cognitive impairment and clinical variables.
The study investigated the potential neuroprotective effects of metformin (MET) on alcohol-induced neurotoxicity in adult Wistar rats. The animals were randomized in four groups (
n
= 10): control, ...alcohol (ALC), ALC + MET, and MET. ALC (2 g/kg b.w.) and MET (200 mg/kg b.w.) were orally administered for 21 days, once daily. For the ALC + MET group, MET was administered 2 h after ALC treatment. On day 22, the open field test (OFT) and elevated plus maze (EPM) were performed. MET improved global activity and increased the time spent in unprotected open arms, decreased oxidative stress, both in the frontal lobe and in the hippocampus, and increased neuroglobin expression in the frontal cortex. Histopathologically, an increased neurosecretory activity in the frontal cortex in the ALC + MET group was noticed. Thus, our findings suggest that metformin has antioxidant and anxiolytic effects and may partially reverse the neurotoxic effects induced by ethanol.
This study investigates the correlation between REM sleep patterns, as measured by the Apple Watch, and depressive symptoms in an undiagnosed population. Employing the Apple Watch for data ...collection, REM sleep duration and frequency were monitored over a specified period. Concurrently, participants' depressive symptoms were evaluated using standardized questionnaires. The analysis, primarily using Spearman's correlation, revealed noteworthy findings. A significant correlation was observed between an increased REM sleep proportion and higher depressive symptom scores, with a correlation coefficient of 0.702, suggesting a robust relationship. These results highlight the potential of using wearable technology, such as the Apple Watch, in early detection and intervention for depressive symptoms, suggesting that alterations in REM sleep could serve as preliminary indicators of depressive tendencies. This approach offers a non-invasive and accessible means to monitor and potentially preempt the progression of depressive disorders. This study's implications extend to the broader context of mental health, emphasizing the importance of sleep assessment in routine health evaluations, particularly for individuals exhibiting early signs of depressive symptoms.
Psychiatrists are often the first to be consulted in patients with anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis. While this disease is rare, psychiatrists need to be aware of its relevant ...fundamental, clinical and therapeutic aspects. We begin by reviewing the connection between anti-NMDAR encephalitis and the glutamate hypothesis of schizophrenia. Next, we focus on the profile of the patient typically afflicted with this disease. Then, we tackle the limited utility of current diagnostic criteria during the early stage of the disease. After reviewing the psychiatric features, we debate the quest for finding specific psychiatric phenotypes that could facilitate early-stage diagnosis. We conclude by discussing the treatment of psychiatric symptoms and disease outcomes. As follows, this paper presents the relevance of anti-NMDAR encephalitis for psychiatrists.
Endogenous depression represents a severe mental health condition projected to become one of the worldwide leading causes of years lived with disability. The currently available clinical and ...non-clinical interventions designed to alleviate endogenous depression-associated symptoms encounter a series of inconveniences, from the lack of intervention effectiveness and medication adherence to unpleasant side effects. In addition, depressive individuals tend to be more frequent users of primary care units, which markedly affects the overall treatment costs. In parallel with the growing incidence of endogenous depression, researchers in sleep science have discovered multiple links between rapid eye movement (REM) sleep patterns and endogenous depression. Recent findings suggest that prolonged periods of REM sleep are associated with different psychiatric disorders, including endogenous depression. In addition, a growing body of experimental work confidently describes REM sleep deprivation (REM-D) as the underlying mechanism of most pharmaceutical antidepressants, proving its utility as either an independent or adjuvant approach to alleviating the symptoms of endogenous depression. In this regard, REM-D is currently being explored for its potential value as a sleep intervention-based method for improving the clinical management of endogenous depression. Therefore, this narrative review represents a comprehensive inventory of the currently available evidence supporting the potential use of REM-D as a reliable, non-pharmaceutical approach for treating endogenous depression, or as an adjuvant practice that could improve the effectiveness of currently used medication.
Our study aimed to assess the longitudinal change of cognitive functions in depressed patients after a 6-month interval free of mood symptoms.
In a longitudinal study, 65 patients diagnosed with ...recurrent major depressive disorder were evaluated twice with neurocognitive tests, during an acute depressed episode and after 6 months of euthymia. The cognitive dimension was assessed with neuropsychological tests of attention and processing speed, memory, verbal fluency, psychomotor speed and executive functions. The severity of depression was evaluated through Hamilton Depression Rating Scale − 17 items. All the results were compared with the outcomes of 35 healthy controls, both in depression and euthymia.
Depressed patients compared to controls displayed significant statistical differences for most cognitive tests applied, verbal and working memory being the most severely impaired. They were still impaired at the second evaluation. Significant differences were noted between the euthymic and control group, too. Between the depression phase and euthymia, patients obtained significant improvement for attention and processing speed, verbal fluency, motor speed and executive functions.
Results from the current study indicate that cognitive impairment is more severe for depressed patients, decreases for euthymic subjects, and lasts longer after depressive symptoms remit.
